child) could require blood transfusion as a result of this 
protocol . 
Stem cell purification : The cells collected by apheresis will be 
purified after harvest in the laboratory by a procedure called 
CD34 selection. The collected cells will be exposed to an anti- 
CD34 antibody (protein) that sticks to the surface of immature or 
CD34 cells. The cells will then be purified by a special column 
that separates the immature cells coated with antibody from more 
mature cells. This antibody and column procedure are 
experimental, but they have been used safely to purify CD34 cells 
from the bone marrow and blood of many patients (over 50) without 
any known side effects. The cells to which the CD34 antibody 
bind include hematopoietic stem cells and progenitor cells. 
GENE TRANSFER PROCEDURE 
Purified CD34 cells will be treated in the laboratory for three 
days in the presence of a virus that has been engineered to 
contain the Fanconi ' s anemia type C gene. Many studies have 
demonstrated that the gene contained in this viral carrier can be 
transferred to the chromosomes of host cells. Once the Fanconi ' s 
anemia gene is in the host cell, the cell will pass the gene to 
its daughter cells. The viral carrier or vector is derived from 
a mouse virus which has been altered specifically so as to be 
unable to reproduce itself. No side effects have been seen in 
over 50 patients who have received cells treated with this type 
of virus vector, although the vector- Fanconi ' s anemia gene 
combination has never before been given to patients. 
This is a very new procedure, and there may be risks that have 
not yet been discovered. Theoretically, there may be an 
increased risk of cancer in cells treated with vectors, but, this 
risk is minimized by making sure that the vector used can not 
reproduce itself once it is inside patient cells. Animals and 
patients receiving cells treated with this type of vector have 
not developed new cancers attributable to the vector. 
Your cells will be grown in several growth factors called IL-3, 
IL-6 and SCF during vector exposure in the laboratory. These 
factors are necessary to keep the CD34 cells alive and to 
increase the chance that the cells will take up the vector. The 
growth factors are experimental drugs and have been given to 
patients. Your cells will be washed thoroughly before giving 
them back to you (your child) . We have not detected growth 
factors on the cells nor in the solution after this washing. 
Stem cell reinfusion : After 3-4 days in culture with vector and 
growth factors, the cells will be collected, washed and given 
back to you (your child) intravenously. You (your child) will 
receive three daily infusions of cells on days 8, 9, 10 after 
beginning G-CSF. Each infusion will take 10-30 minutes, and you 
(your child) will be monitored closely for side effects during 
and after the infusions. We do not expect any side effects, but 
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